Hybrid Concurrency Control Method in Firm Real-Time Databases
نویسنده
چکیده
Real-time database system must meet time constraints in addition to the integrity constraints. Concurrency control is one of the main issues in the studies of real-time database systems. Traditional concurrency control methods use serializability as the correctness criterion when transactions are executed concurrently. However, strict serializability as the correctness criterion is not always suitable in real-time databases. Instead, correctness requirements vary from one type of transactions to another and from one data type to another. In this paper we propose a concurrency control method where used concurrency control is based on method defined on table creation. Transactions can freely use tables based on pessimistic concurrency control, optimistic concurrency control or nocheck concurrency control based on application needs. Proposed method is evaluated and tested in prototype implementation of real-time database system for telecommunications.
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